Dual mode fuze explosive train

ABSTRACT

A dual mode fuze explosive train which comprises the combination of a superquick firing pin assembly and an inertial firing pin assembly whereby the inertial pin comes forward to initiate the stab primer when the fuze hits a soft target and the superquick firing pin is driven into a stab detonator thereby initiating the end initiator when a hard target is struck.

United States Patent Inventor Rodney A. Bernardin Wayzeta, Minn. Appl. No. 61,129 Filed Aug. 5, 1970 Patented Jan. 1 l, 1972 Assignee The United States of America as represented by the Secretary of the Navy DUAL MODE FUZE EXPLOSIVE TRAIN 1 Claim, 3 Drawing Figs.

[1.8. CI 102/74, 102/7.2, 102/76, l02/85.6

Int. Cl F42c l/00 Field 021 Search l02/70, 71,

[56] References Cited UNITED STATES PATENTS 1,347,716 7/1920 sem 16 102/74 1,531,717 3 1925 Remondy.... 102 74 1,751,616 3 1930 Brayton 102 74 1,916,245 7 1933 Woodberry 102/74 Primary Examiner-Samuel W. Engle Attorneys-R. S. Sciascia and Roy Miller ABSTRACT: A dual mode fuze explosive train which comprises the combination of a super-quick firing pin assembly and an inertial firing pin assembly whereby the inertial pin comes forward to initiate the stab primer when the fuze hits a soft target and the superquick firing pin is driven into a stab detonator thereby initiating the end initiator when a hard target is struck.

PATENTEU JAN? Y I972 RODNEY A. BERNARDIN ROY MILLER ATTORNEY.

DUAL MODE FUZE EXPLOSIVE TRAIN BACKGROUND OF THE INVENTION The present invention relates to a dual mode fuze explosive tram.

To meet the needs of the overall perfonnance of guided missiles, much time has been expended on exploration of new fuze design, improved fuze design, improved fuze systems for specific applications, and technical evaluation of fuze systems. The present invention provides a dual mode fuze explosive train which improves the performance of the antipersonnel/antimaterial cluster weapons. The general purpose is to provide a fuzing system which is simple, inexpensive and reliable. The invention provides such a system which will initiate detonation of a warhead if either a hard target is hit or a soft target is hit.

DESCRIPTION OF THE DRAWING FIG. 1 is an enlarged view in section of a portion of a bomblet incorporating the present invention;

FIG. 2 is an end view ofthe fuze housing; and

FIG. 3 shows the end cap which covers the fuze section of the bomblet.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing there is shown in FIG. 1 a bomblet in partial section which incorporates the present invention. The bomblet comprises a casing 11 which is formed of notched steel wire high explosive 14 such as HMX, or RDX. A dual fuze explosive train assembly designated generally as numeral 15 is secured by suitable means to the nose end of said bomblet casing 11 and is adapted to initiate the booster 16 which is positioned at the apex of cone liner l3. Booster 16 is connected to the fuze train assembly 15 by a detonating transfer train 17 and end initiator 34. The dual fuze explosive train assembly 15 comprises a fuze housing 18 provided with a cavity into which is positioned a cylindrically shaped rotor 19 mounted for rotation about its longitudinal axis. A gear train mechanism 20 is mounted to the side of fuze housing 18 and is suitably attached to rotor 19 for driving said rotor. Rotor 19 has two vertical bores near each end one which contains a stab detonator as shown at 21 and the other a stab primer 22 as shown. Also rotor 19 is provided with a transverse bore containing a delay composition 23 as shown between the two vertical bores. Rotor 19 is positioned in the fuze housing 18 so that the end containing stab detonator 21 is adjacent a firing pin retainer 24 which is fixed in fuze housing 18. The end containing stab primer 22 is adjacent an inertia firing pin assembly 25 which is also fixed in said fuze housing as shown. Rotor 19 is positioned so as to be out of line or in a safe position and is driven to the armed position shown. The primer 22 and detonator 21 which when actuated conduct the detonation wave through the end initiator 34 and detonating transfer train 17 to the booster 16 which in turn detonates shaped charge 12.

The nose end 26 of fuze housing 11 shown in FIG. 2 is provided with a lever plate 27 positioned adjacent firing pin retainer 24, which moves to actuate said pin when a hard target is struck.

Fuze housing 18 is provided with a nose probe 28 as shown in FIG. 3 which slides firmly over the outside of fuze housing 18 and is a part of bomblet casing 11. As shown nose probe 28 is provided with a hollow cone-shaped end having a slidably mounted striker 29 positioned therein which is secured by a pair of restraining pins 30.

Inertia firing pin assembly 25 comprises a delay firing inertia weight 32, and a firing pin 33 which will drive into the stab primer 22 when a soft target is hit. Stab primer 22 initiates a propellant charge 35 and the pyrotechnic time delay composition 23 which burns to the sensitive end of and initiates the stab detonator 21. Ultimately the stab detonator fires and transmits a detonation wave via the end initiator 34 and transfer train 17 to the booster l6 and thence to the shaped char e ex losive resulting in an airburst of the warhead.

W en t e bomblet impacts a hard target such as armor,

metal clad body, rock or the like, the striker 29 on nose probe 28 defeats two restraining shear pins 30 and pushes against lever plate 27 positioned on fuze housing 18 which actuates superquick firing pin 31 held in retainer 24. Firing pin 31 now stabs detonator 21 which causes it to explode sending a detonation signal via the end initiator 34 and transfer train 17 to the booster 16 which transmits the wave to the main charge 12. The target will then be subjected to shaped charge warhead action.

What is claimed is:

l. A dual mode hard and soft target fuze explosive assembly comprising:

a fuze housing defining a cavity;

a lever plate positioned at the end of said housing;

a rotor mounted for rotation about its longitudinal axis within said cavity; said rotor being provided with two internal vertical recesses near each end and a centrally positioned transverse recess;

a gear means positioned outside said housing secured to said rotor and adapted to drive said rotor;

explosive means filling said recesses in said rotor comprising a stab primer composition in the vertical recess on the end adjacent said gear means; a stab detonator composition in the recess at the other end of said rotor and a pyrotechnic delay composition filling said transverse recess between the two vertical recesses;

a fixed firing pin retainer positioned in said housing adjacent said stab detonator and a firing pin means slidably mounted in said retainer and held in a nonfiring position;

means outside said housing which moves said lever plate against said firing pin means urging said pin from said retainer to a firing position when a hard target is hit;

an inertial firing pin assembly in a fixed position in said housing adjacent said stab primer composition; said assembly comprising an inertia weight and a firing pin adjacent thereto whereby when a soft target is struck said weight drives said pin into the stab primer which initiates said pyrotechnic time delay causing initiation of the sensitive end of said stab detonator and subsequent firing of said detonator which transmits detonation waves therefrom. 

1. A dual mode hard and soft target fuze explosive assembly comprising: a fuze housing defining a cavity; a lever plate positioned at the end of said housing; a rotor mounted for rotation about its longitudinal axis within said cavity; said rotor being provided with two internal vertical recesses near each end and a centrally positioned transverse recess; a gear means positioned outside said housing secured to said rotor and adapted to drive said rotor; explosive means filling said recesses in said rotor comprising a stab primer composition in the vertical recess on the end adjacent said gear means; a stab detonator composition in the recess at the other end of said rotor and a pyrotechnic delay composition filling said transverse recess between the two vertical recesses; a fixed firing pin retainer positioned in said housing adjacent said stab detonator and a firing pin means slidably mounted in said retainer and held in a nonfiring position; means outside said housing which moves said lever plate against said firing pin means urging said pin from said retainer to a firing position when a hard target is hit; an inertial firing pin assembly in a fixed position in said housing adjacent said stab primer composition; said assembly comprising an inertia weight and a firing pin adjacent thereto whereby when a soft target is struck said weight drives said pin into the stab primer which initiates said pyrotechnic time delay causing initiation of the sensitive end of said stab detonator and subsequent firing of said detonator which transmits detonation waves therefrom. 